OBJECTIVE To test various nuclear transfer strategies to generate genetically identical rhesus monkeys. RESULTS The role of Dr. ThomsonUs laboratory in this project is to derive new rhesus ES cell lines and provide them to the Oregon Regional Primate Center for nuclear transfer experiments. During 1998, we continued weekly shipments of early passage rhesus ES cell lines, and derived a new rhesus ES cell line. FUTURE DIRECTIONS We anticipate that we will derive 6 new rhesus ES cell lines per year and provide them to the Oregon Regional Primate Research Center. FUNDING NIH 1R24RR12804